1. Field of the Invention
The present invention, in certain respects, may relate to the manufacture of magnetic disk drives. In other respects, the present invention may relate to methods and systems for determining when a magnetic disk drive read/write head is subjected to undesired PTP and for taking corrective action.
2. Description of Background Information
Magnetic disk drives are being manufactured with increased access speeds and storage capacities. Manufacturers of these (present day and future) improved-performance magnetic disk drives have decreased the distance between the magnetic disk drive's read/write heads and its disk media. As a result, slight variations in the positioning or dimensions of the heads or of the disk media can cause the heads and the disk media to collide. For example, such a collision can be caused by protrusion of the pole tips of the write portion of a given read/write head, a phenomenon referred to as pole tip protrusion (PTP).
PTP happens when the disk head heats up causing part of the head's air bearing surface (ABS) to protrude and touch the disk. When this happens, a number of problems can result. Some such problems include off tracks, servo address mark (SAM) and gray code errors, head damage, and disk damage.